text: #include <bits/stdc++.h>
  using namespace std;
  
  const int MOD = 1e9 + 7;
  const int MAXN = 100;
  
  int memo[MAXN + 1];
  
  int fibo(int n) {
  	if (memo[n] > 0) return memo[n];
  	if (n < 3) return 1;
  	return memo[n] = (fibo(n - 1) + fibo(n - 2)) % MOD;
  }
  
  int main() {
  	int N;
  	cin >> N;
  	cout << fibo(N) << endl;
  }